Until four years ago, rugby and football were banned at Croke Park. Owned by the Gaelic Athletic Association, the ground was built in 1884 to house and protect Ireland's indigenous sports of hurling, camogie and Gaelic football. But with Ireland's football and rugby union headquarters, Lansdowne Road, closed for a £358m redevelopment due to be completed in 2010, the GAA have opened Croke's doors (temporarily) to these foreign sports.

1. The floodlights

The GAA spent £3.5m installing floodlights to enable international rugby and football to be played at Croke Park. It wasn't a bad investment: they will earn around £34m for opening up the ground to the Football Association of Ireland and the Irish Rugby Football Union until 2010. The rent charged for the ground alone is £1.1m per international game, while the television fee for a single football match, between Ireland and Germany in 2007, netted £8.8m.

2. The Hogan Stand

Built in 1924, the stand was named after Gaelic footballer and Tipperary captain Michael Hogan, who had been shot dead at the ground four years earlier. On 21 November 1920, the IRA killed 14 British intelligence officers in Dublin; the same day the British Auxiliary Division stormed Croke Park in response, while Tipperary played Dublin, killing 13 spectators and Hogan. The stand now houses the media centre, corporate ticket holders and general spectators.

With its capacity of 82,300, Croke Park is the fourth largest stadium in Europe behind Camp Nou, Wembley, and Ukraine's national sports complex, the Olimpiysky.

3. The sponsors

Guinness is the somewhat predictable sponsor of the Irish rugby union team. Technically, "the black stuff" isn't actually black, but a dark ruby red colour due to some of the malted barley being roasted. Ten million pints are bought worldwide every day; a recent survey found that 70% of Irish respondents "felt closer to Guinness" as a result of their sponsorship of the team. Heartwarming.

4. The band

The combined Army and Garda Band are responsible for belting out the anthems before each international game. The Irish Football Union and the Northern Football Union of Ireland formally united in 1879, but it wasn't until 1995 that songwriter Phil Coulter composed Ireland's Call as their official rugby anthem to avoid having to choose between the Republic of Ireland's The Soldier's Song, and God Save the Queen, for Northern Ireland.

As a music venue, Croke Park has hosted some even bigger names than the Army and Garda band - including U2, the Police, Westlife and Neil Diamond.

5. The pitch

Designed with Gaelic games in mind, the pitch - at 144.5m x 88m - is bigger than the usual rugby or football field, so the crowd are further away from the action than normal. The grass on it was created specially, combining natural rye grass with synthetic artificial fibres to avoid bald patches, and it can drain up to 12 inches of water in less than an hour.